Clean distillates streams that contain no or nil sulfur, nitrogen, or aromatics, are, or will likely be in great demand as jet fuel or in blending jet fuel. Clean distillates having relatively high lubricity and stability are particularly valuable. Typical petroleum derived distillates are not clean, in that they typically contain significant amounts of sulfur, nitrogen, and aromatics. In addition, the severe hydrotreating needed to produce fuels of sufficient stability often results in a fuel with poor lubricity characteristics. These petroleum derived clean distillates produced through severe hydrotreating involve significantly greater expense than unhydrotreated fuels. Fuel lubricity, required for the efficient operation of the fuel delivery system, can be improved by the use of approved additive packages. The production of clean, high cetane number distillates from Fischer-Tropsch waxes has been discussed in the open literature, but the processes disclosed for preparing such distillates also leave the distillate lacking in one or more important properties, e.g., lubricity. The Fischer-Tropsch distillates disclosed, therefore, require blending with other less desirable stocks or the use of costly additives. These earlier schemes disclose hydrotreating the total Fischer-Tropsch product, including the entire 700.degree. F.-fraction. This hydro-treating results in the complete elimination of oxygenates from the jet fuel.
By virtue of this present invention small amounts of oxygenates are retained, the resulting product having high lubricity. This product is useful as a jet fuel as such, or as a blending stock for preparing jet fuels from other lower grade material.